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WIGGLING 'LITE' IN GUEST MODE

Random Source Random Source Question
MUFF WIGGLER Forum Index -> Music Tech DIY  
Author Random Source Random Source Question
Reese P. Dubin
Redundant right?
My right hand column is working as I expect, very nicely noisy and grainy.
However I am clearly missing something regarding the function of the left column. How the heck do I patch this to make it go? I have many SSGs and am clear on them, but what gets the ball rolling here?
johnnywoods
When I first built mine, only one half of the module worked. I can't remember what I did to fix it, but it was a super minor thing.

Also, check the trimpots to make sure the range is set appropriately.
Reese P. Dubin
If somebody can briefly explain how the left side is meant to work it will probably help a lot in figuring it out. I get a steady pulse from the pulse jack, but the other controls seem to not have any effect, smooth and stepped outs just have a bit of an offset rather than outputs respective of their names.
Have fiddled with the trims extensively.
Gonna hate giving this to its owner very frustrating very frustrating
cygmu
I don't have this module so could be wrong, but my understanding is that it is supposed to work just like the SSG Random Voltage patch http://www.serge-fans.com/wiz_SSG3.htm but without the need to patch anything.

That is, you should get slewing random voltages from the Smooth output, stepped random voltages from the Stepped output, and random pulses from the Pulse output, all without patching anything in. If I understand correctly, turning the rate up full should give the full range of outputs.

But as I say, never tried this module so I don't know for sure. You could try emailing Ralf to at least get a proper description of how it's meant to work.
nordlead
cygmu wrote:
I don't have this module so could be wrong, but my understanding is that it is supposed to work just like the SSG Random Voltage patch http://www.serge-fans.com/wiz_SSG3.htm but without the need to patch anything.

That is, you should get slewing random voltages from the Smooth output, stepped random voltages from the Stepped output, and random pulses from the Pulse output, all without patching anything in. If I understand correctly, turning the rate up full should give the full range of outputs.

But as I say, never tried this module so I don't know for sure. You could try emailing Ralf to at least get a proper description of how it's meant to work.


Yes, that's correct - the RS is an SSG (pre)patched as Random Voltage Generator (but you need the "hot" coupler for that if you want to manually patch it). First I'd check that the S/H Source is working as expected, generating a "dirty saw". If you have an R*S SSG (with the hot coupler) you should be able to patch the SSG to behave like the RS.

I posted scope shots showing the levels in my reference unit > here.
Reese P. Dubin
Several weeks later I still have been unable to tune this in and get anything from the smooth and stepped outs. Starting to lose my mind, dealing with SMD and no schematic is mildly painful. very frustrating I have tried every method of trimming I can imagine, and triple checked every connection thoroughly

So answer me this, should the pulse output be putting out a truly random array of pulses? I am getting a steady train that is related to the rate/CV rate. The LED never pulses or lights, except on startup it sometimes does that power up LED thing. I was/am expecting RANDOM

Last piece of the puzzle on this amazing panel. HELP!
nordlead
Reese P. Dubin wrote:

So answer me this, should the pulse output be putting out a truly random array of pulses?


Yes, the PULSE out should deliver random pulses (gates) of varying length:



Changing the RATE should change the speed of the random pulse train.

To sort this out, I recommend going step by step.

(1) Check that the S/H SRC generates the proper starting signal ("dirty saw").
(2) Make sure the RS (SSG) pcb works correctly in an SSG slot (i.e. as an SSG).
(3) If you have another R*S SSG you can try to patch it as a Random Source,
using the S/H SRC and the "hot" Coupler Out on the SSG:

SH/SRC into the IN of the Stepped side of the SSG. COUPLER into SAMPLE on the Stepped side and also into IN on the Smooth side. The random pulses (0 to 5V) should available at the normal COUPLER and speed / randomness can be adjusted using the RATE knobs on both sides (turn Stepped rather up and Smooth rather down).

If that works with another SSG, you know that the S/H SRC is good.

Send me an email if this does not work - also, happy to look at scope shots of your S/H SRC.
the bad producer
Same problem here - just reading back through the other thread - Reese, did you get anywhere?
Leturbo
I am also having this exact same issue (as Reese describes). SSG PCB used for the Random Source works just fine in the SSG slot (when patched)... noise section is fine, S/H SRC looks as Ralf described (dirty saw)....

LED only works on power ON, then goes out.... signal coming out of smooth and stepped outputs is.... well it barely registers, but when I get in close enough:



So there is something there but... mean voltage of -560mV .... this is clearly not working properly for a smooth or steeped output, no? What is the LED on this module supposed to indicate?

I tried this PCB in the SSG slot, and once it was patched, smooth and stepped sides worked as expected.

Has anyone had any luck with this? According to this thread I am the third person with the issue... so either we're all making the same dumb mistake or there are some weird issues with the SSG PCB when in the Random Source slot...
the bad producer
I think I figured it out, but I'm afraid I can't remember what I did as it was a job for a client and didn't hang around, I'll try and find my notes on the build but I have a feeling they don't exist, sorry!
Reese P. Dubin
that would be awesome
have tried every trim combination I can imagine to no avail
nordlead
Here's an except of a post I made in another thread a while ago:

"It's been a while that I built mine and wrote the docs. Still as far as I remember I took a very straightforward calibration approach: calibrated the SSG as described to get the max range. Then I believe I simply calibrated the noise side so that the lower S/H Out is (fairly) bipolar - my scope now shows an average of appr. -500mV. The (white) S/H out shows an average of appr. 2.3V, i.e. seems to sit above the 0V line, i.e. most of the lowest points are around 1V, some occasional spikes go lower (this is random!):


My S&H SRC looks like this:



If your S/H output looks different, try adjusting it using the S/H trimmer till it looks similar."

---

To figure out what might be going on, it would be helpful to know how far you get with this approach I suggested earlier:

(1) Check that the S/H SRC generates the proper starting signal ("dirty saw").
(2) Make sure the RS (SSG) pcb works correctly in an SSG slot (i.e. as an SSG).
(3) If you have another R*S SSG you can try to patch it as a Random Source,
using the S/H SRC and the "hot" Coupler Out on the SSG:

SH/SRC into the IN of the Stepped side of the SSG. COUPLER into SAMPLE on the Stepped side and also into IN on the Smooth side. The random pulses (0 to 5V) should available at the normal COUPLER and speed / randomness can be adjusted using the RATE knobs on both sides (turn Stepped rather up and Smooth rather down).

If that works with another SSG, you know that the S/H SRC is good.

So before addressing any Random Source issues, it is essential to make sure the white noise is fine and the S/H SRC ("dirty saw") as well. Feel free to send me an email with scope shots.

Leturbo, just to be sure, what exactly does your scope shot above show? Smooth Out of the RS side(??)
GryphonP3
Has anybody ever been able to solve this? I never use this module, and just realized today that I have the exact same issue - LED shoots once on power up, all noise and S/H source and S/H outputs and button and trig in jack work perfectly, it works as an SSG, but the smooth and stepped random outputs are just a constant high voltage which changes level with the rate knob after the first cycle on power up falls. When I press the large SMT cap or the middle pin headers with my finger, it comes to life and works perfectly. I have tested continuity on all pin headers and they are fine. I have tested continuity on all TH parts that I placed and they are fine. Trimmers affect all the working parts properly.. This is driving me crazy.. It seems like there is a wrong value installed in the prepopulated SMT parts or something. Used a PN4250 for the noise transistor - Tried swapping out a few other transistors today and they all end in the same result.

I followed all of Ralf's instructions above, the noise and S/H source are working perfectly. Smooth and Stepped out just show a constant DC voltage which rised and falls when I turn the rate knob up or down.
GryphonP3
This is really, really bugging me. Has anybody ever made any developments on this issue? Really weird that so many people are having the exact same problem.
Reese P. Dubin
still floating out here on this

just saw your post from april, you are saying you can get the entire circuit to work properly if you push on an SMT cap?? i never tried that

i find this a major bummer. i think RS is fucking golden but there is CLEARLY a physical error somewhere on some of these prebuilt boards. nobody seems to want to address it very frustrating I have never spent anywhere close to the amount of time on anything of any size as I have on this one board.

is your random pulse out an insane high frequency as well?? on the one i have here it only comes down to what would be useful for anything when i am pumping -5v into it.

there IS a fault in some of these boards. Dead Banana
js213
This probably won't help anyone, but here is what I get from the random section on the Edelweiss I just built:

Pulse Out

Stepped Out

Smooth Out




js213
Here's my board incase anyone wants a look.

GryphonP3
Reese P. Dubin wrote:


is your random pulse out an insane high frequency as well?? on the one i have here it only comes down to what would be useful for anything when i am pumping -5v into it.

there IS a fault in some of these boards. Dead Banana


Yep, exact same behavior. So fast it just sounds like a digital noise module. super crunchy bitcrushed oscillator sound. I actually bought a new main PCB for this off of Ralf and it has the exact same behavior as the old one. Maybe the problem lies within the control board? It's really weird, all other functions work perfectly, and it works while patched into the main SSG.
jln
js213 wrote:
Here's my board incase anyone wants a look.



Thanks a lot ! I worked without success today again on the board as I too have some problems (random source board works fine under SSG but got no signal for at white and pink noise outputs, s/h src outputs a clean saw).

I just realize looking at your photo that I think I put the transistor in the wrong direction. I naively followed the diagram printed on the board...

I'll try to reverse the transistor tomorrow. Or should I assume that it is now dead ?
js213
jln wrote:
I just realize looking at your photo that I think I put the transistor in the wrong direction. I naively followed the diagram printed on the board...

I'll try to reverse the transistor tomorrow. Or should I assume that it is now dead ?


I did that too on my first one. Reversing it should fix it. I was able to use the same one. If it still doesn't work, try a new one.
jln
js213 wrote:

I did that too on my first one. Reversing it should fix it. I was able to use the same one. If it still doesn't work, try a new one.


Hi js213. Thanks for your help ! I reversed the transistor and it now obviously works fine !

Shame on me how much time did I spent on this stupid newbie issue... :-$

That being fixed, I still have a few issues: both smooth and stepped outputs output nothing (steady 0~ voltage). AM I right understanding that these should work as pre-patched SSG side ?

What puzzles me is that the board works fine when plugged in the left SSG side on the module but not when plugged in the RS side. I guess I have a problem with the bottom section of the RS board or with the panel board but so far haven't really found anything...
js213
With that PCB used in multiple configurations, is there a chance that it's missing some components when used on the RS side (e.g. it's set up to be used as an SSG, rather than a Random Source?) I can get better shots of mine, plus my Carnivore if it would help in comparing the components installed.
jln
js213 wrote:
With that PCB used in multiple configurations, is there a chance that it's missing some components when used on the RS side (e.g. it's set up to be used as an SSG, rather than a Random Source?) I can get better shots of mine, plus my Carnivore if it would help in comparing the components installed.


mm... While I'm not sure if it may be the issue, for sure I can spot a few differences between your RS board and mine (although both v1.02).

Mine actually has one additional component hmmm.....

Reese P. Dubin
[quote="jln"]
js213 wrote:


What puzzles me is that the board works fine when plugged in the left SSG side on the module but not when plugged in the RS side. I guess I have a problem with the bottom section of the RS board or with the panel board but so far haven't really found anything...


When plugged in to the SSG slot it still has to be patched to work (cycle/trig)
It has always felt to me that there is some sort of fault when in the RS slot, where the connections that are manually connected ARE NOT properly natively connected. Lack of a schematic and any word from Ralf for over a year makes this essentially/partially bricked.

I ASSUME (having never had it working properly) that the random trigs would be the trigger/timing source for smooth/stepped. But this still leaves the cycle connection to be accounted for.

GRRR
jln
Reese P. Dubin wrote:

When plugged in to the SSG slot it still has to be patched to work (cycle/trig)
It has always felt to me that there is some sort of fault when in the RS slot, where the connections that are manually connected ARE NOT properly natively connected. Lack of a schematic and any word from Ralf for over a year makes this essentially/partially bricked.

I ASSUME (having never had it working properly) that the random trigs would be the trigger/timing source for smooth/stepped. But this still leaves the cycle connection to be accounted for.

GRRR


I have the same impression seeing how it behaves & reading the thread again.

Out of curiosity, what does your Random source board look like ? Not sure if that could be the culprit here, but I'm surprised seeing that [js213]'s working board doesn't have a component I have on mine (the one in the center of the board).

Is your PCB like mine or like [js213]'s ?
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